Protein Array Guides Nanocrystal Growth

Two years ago, F. Akif Tezcan of the University of California, San Diego, and coworkers showed that an electron-transfer protein could self-assemble via zinc ion coordination into one- and two-dimensional arrays (C&EN, March 12, 2012, page 9). At the time, nanotechnologist Chengde Mao of Purdue University commented that applications of the work could include using the metal-linked protein arrays “as templates for nanofabrication.” Tezcan, Jeffrey D. Brodin, and coworkers have now demonstrated just that (Proc. Natl. Acad. Sci. USA 2014, DOI: 10.1073/pnas.1319866111). The researchers show that a cytochrome protein in a metal-based array is much more stable to heat and organic solvents than the native protein and that its light-driven redox activity can be used to control inorganic nanocrystal growth. Stable arrays of other proteins and enzymes with different functions could also potentially be used. Manuel A. Navia of Oxford Bioscience Partners, who developed cross-linked enzyme crystals, says the new technology “still has a ways to go, but I am both curious and excited about the never-before-seen polymers and other interesting materials it could eventually be used to create.”